抄録
Variations of periods in superficial seismic waves were observed with various charge amounts. Those seismic waves were considered to be the zeroth and the first orders of RAYLEIGH and SEZAWA-waves respectively, due to the superficial layer in the experimental ground. Each period was found to have its own asymptotic value which was seen to satisfy the quarter wave-length law discussed previously by the present author. Frequency characteristics at the origin of seismic waves were also considered.
